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Reindeer summer pastures and ultraviolet radiation (UV)
2002
Soppela, P. (University of Lapland, Rovaniemi (Finland). Arctic Centre) | Turunen, M. | Heiskari, U. | Forbes, B. | Aikio, P. | Magga, H. | Sutinen, M. L. | Ahman, B. | Helle, T. | Nieminen, M. | Kyro, E. | Lakkala, K. | Huttunen, S. | Uhlig, C.
The aim of the proposed research is to investigate the effects of UV-radiation on chemical composition, palatability and digestibility of summer pasture plants of reindeer. The studies are planned to be conducted in natural peatland ecosystems with (I) enhanced UV-B radiation, provided by UV-B lamps and (II) with UV-filtration experiments with the same plant species in reindeer pastures in the Lappi Reindeer Herding Cooperative in Eastern Finnish Lapland. The results will provide information about the effects of ambient and enhanced UV radiation on summer pastures of reindeer and can be used to evaluate their consequences on reindeer management
显示更多 [+] 显示较少 [-]Vertical distribution and temporal dynamics of dissolved 137Cs concentrations in soil water after the Fukushima Dai-ichi Nuclear Power Plant accident
2017
Iwagami, Sho | Onda, Yūichi | Tsujimura, Maki | Hada, Manami | Pun, Ishwar
Radiocesium (137Cs) migration from headwater forested areas to downstream rivers has been investigated in many studies since the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, which was triggered by a catastrophic earthquake and tsunami on 11 March 2011. The accident resulted in the release of a huge amount of radioactivity and its subsequent deposition in the environment. A large part of the radiocesium released has been shown to remain in the forest. The dissolved 137Cs concentration and its temporal dynamics in river water, stream water, and groundwater have been reported, but reports of dissolved 137Cs concentration in soil water remain sparse.In this study, soil water was sampled, and the dissolved 137Cs concentrations were measured at five locations with different land-use types (mature/young cedar forest, broadleaf forest, meadow land, and pasture land) in Yamakiya District, located 35 km northwest of FDNPP from July 2011 to October 2012. Soil water samples were collected by suction lysimeters installed at three different depths at each site. Dissolved 137Cs concentrations were analyzed using a germanium gamma ray detector. The dissolved 137Cs concentrations in soil water were high, with a maximum value of 2.5 Bq/L in July 2011, and declined to less than 0.32 Bq/L by 2012. The declining trend of dissolved 137Cs concentrations in soil water was fitted to a two-component exponential model. The rate of decline in dissolved 137Cs concentrations in soil water (k1) showed a good correlation with the radiocesium interception potential (RIP) of topsoil (0–5 cm) at the same site. Accounting for the difference of 137Cs deposition density, we found that normalized dissolved 137Cs concentrations of soil water in forest (mature/young cedar forest and broadleaf forest) were higher than those in grassland (meadow land and pasture land).
显示更多 [+] 显示较少 [-]Multicorrelation models and uptake factors to estimate extractable metal concentrations from soil and metal in plants in pasturelands fertilized with manure
2012
Lopes, Carla | Herva, Marta | Franco-Uría, Amaya | Roca, Enrique
Environmental risk assessment (ERA) is a useful methodology to estimate the possible adverse effects to human health due to contaminants exposure. In the case of agricultural scenarios, this method requires knowing the concentrations of contaminants in soil solution and vegetation, among other parameters. This study aimed to develop multicorrelation models to estimate metal extractable from soil as a function of total metal concentration in soil and soil properties in a cattle manure application scenario. It also aimed to estimate metal concentrations in plant by soil–plant uptake factors (UF). All the multicorrelation models obtained were significant, ranging R² values from 0.44 for Cd to 0.92 for Cu. Soil–plant UF were an adequate method for the estimation of metal concentration in plant, since the relationship between the soil–plant UF and the extractable metal concentration from soil was significantly described by a power model, for all the heavy metals.
显示更多 [+] 显示较少 [-]Assessing the leaching of cadmium in an irrigated and grazed pasture soil
2022
McDowell, R.W.
To decrease the concentration of the toxic metal cadmium (Cd) in topsoil, and the human food chain, many countries have limited the Cd concentration allowed in phosphorus (P) fertilisers. However, to inform those limits we need accurate estimates of Cd leaching from established farming systems. Different soil layers were sampled to 2000 mm depth of a long-term trial that had applied 22.5 kg P ha⁻¹ yr⁻¹ for 67 years to grazed pastures that received either no irrigation or were irrigated when soil moisture fell below 10 or 20%. The annual yield of Cd leaching from the top 150 mm of soil to the 151–250 mm layer was between 1.1 and 1.8 g ha⁻¹ with Cd leaching increasing with the frequency of irrigation. The rate of Cd accumulation measured to 2000 mm was within the mean and standard error estimated for treatments using a mass balance approach. Estimates of annual Cd leaching loss were like those established from field trials measuring leaching events over a year (0.3–1.8 g ha⁻¹) with a similar rate of P application (9–24 kg P ha⁻¹ yr⁻¹). Using a Cd leaching rate of 1.8 g ha⁻¹ yr⁻¹ and P applications rates of 22.5 kg P ha⁻¹, topsoil Cd concentrations may stop increasing if Cd concentrations in P fertiliser can be maintained at < 72 mg Cd kg⁻¹ P.
显示更多 [+] 显示较少 [-]Antibiotic resistance genes and bacterial communities in cornfield and pasture soils receiving swine and dairy manures
2019
Chen, Zeyou | Zhang, Wei | Yang, Luxi | Stedtfeld, Robert D. | Peng, Anping | Gu, Cheng | Boyd, Stephen A. | Li, Hui
Land application of animal manure could change the profiles of antibiotic resistant bacteria (ARB), antibiotic resistance genes (ARGs) and bacterial communities in receiving soils. Using high-throughput real-time quantitative PCR and 16S rRNA amplicon sequencing techniques, this study investigated the ARGs and bacterial communities in field soils under various crop (corn and pasture) and manure (swine and dairy) managements, which were compared with those of two non-manured reference soils from adjacent golf course and grassland. In total 89 unique ARG subtypes were found in the soil samples and they conferred resistance via efflux pump, cellular protection and antibiotic deactivation. Compared to the ARGs in the golf course and grassland soils (28 and 34 subtypes respectively), manured soils generally had greater ARG diversity (36–55 subtypes). Cornfield soil frequently receiving raw swine manure had the greatest ARG abundance. The short-term (one week) application of composted and liquid swine manures increased the diversity and total abundance of ARGs in cornfield soils. Intriguingly the composted swine manure only marginally increased the total abundance of ARGs, but substantially increased the number of ARG subtypes in the cornfield soils. The network analysis revealed three major network modules in the co-occurrence patterns of ARG subtypes, and the hubs of these major modules (intl1-1, vanC, and pncA) may be candidates for selecting indicator genes for surveillance of ARGs in manured soils. The network analyses between ARGs and bacteria taxa revealed the potential host bacteria for the detected ARGs (e.g., aminoglycoside resistance gene aacC4 may be mainly carried by Acidobacteriaceae). Overall, this study highlighted the potentially varying impact of various manure management on antibiotic resistome and microbiome in cornfield and pasture soils.
显示更多 [+] 显示较少 [-]Mitigation of N2O emissions from urine treated acidic soils by liming
2019
Shaaban, Muhammad | Hu, Ronggui | Wu, Yupeng | Younas, Aneela | Xu, Xiangyu | Sun, Zheng | Jiang, Yanbin | Lin, Shan
Nitrous oxide (N2O) is a devastating greenhouse gas mainly released from soils to the atmosphere. Pasture soils, particularly acidic in nature, are large contributors of atmospheric N2O through deposition of urine-N. Devising strategies for reducing N2O emissions in acidic soils are the utmost need of the time. Therefore, the present study was carried out to investigate the possible efficacy of dolomite application to reduce N2O emissions from urine treated acidic soil. Application of urine to soil enlarged the production of NH4+-N, NO3−-N, microbial biomass C (MBC) and dissolved organic C (DOC), resulting in higher N2O emissions as compared to the control (soil only). The highest N2O emission rate (1.35 μg N2O-N kg−1 h−1) and cumulative flux (408 μg N2O-N kg−1) occurred in urine only treated soil. Dolomite addition, especially higher application dose, greatly reduced N2O emissions through improved soil pH. The results suggest that increasing pH of acidic soils is a good applicable approach for reducing N2O emissions from urine-treated soils.
显示更多 [+] 显示较少 [-]N-fixation in legumes – An assessment of the potential threat posed by ozone pollution
2016
Hewitt, D.K.L. | Mills, G. | Hayes, F. | Norris, D. | Coyle, M. | Wilkinson, S. | Davies, W.
The growth, development and functioning of legumes are often significantly affected by exposure to tropospheric ozone (O3) pollution. However, surprisingly little is known about how leguminous Nitrogen (N) fixation responds to ozone, with a scarcity of studies addressing this question in detail. In the last decade, ozone impacts on N-fixation in soybean, cowpea, mung bean, peanut and clover have been shown for concentrations which are now commonly recorded in ambient air or are likely to occur in the near future. We provide a synthesis of the existing literature addressing this issue, and also explore the effects that may occur on an agroecosystem scale by predicting reductions in Trifolium (clovers) root nodule biomass in United Kingdom (UK) pasture based on ozone concentration data for a “high” (2006) and “average” ozone year (2008). Median 8% and 5% reductions in clover root nodule biomass in pasture across the UK were predicted for 2006 and 2008 respectively. Seasonal exposure to elevated ozone, or short-term acute concentrations >100 ppb, are sufficient to reduce N-fixation and/or impact nodulation, in a range of globally-important legumes. However, an increasing global burden of CO2, the use of artificial fertiliser, and reactive N-pollution may partially mitigate impacts of ozone on N-fixation.
显示更多 [+] 显示较少 [-]Metal exposure in cows grazing pasture contaminated by iron industry: Insights from magnetic particles used as tracers
2016
Ayrault, Sophie | Catinon, Mickaël | Boudouma, Omar | Bordier, Louise | Agnello, Gregory | Reynaud, Stéphane | Tissut, Michel
Magnetic particles (MP) emitted by an iron smelter were used to investigate the exposure of cows grazing on a grassland polluted by these MP and by large amounts of potentially toxic elements (PTE). The morphology as well as the chemical composition of the MP separated from cow dung were studied. Large amounts of typical MP were found (1.1 g kg−1 dry weight) in the cow dung sampled from the exposed site, whereas these particles were absent from the reference unpolluted site. The ingested MP were mainly technogenic magnetic particles (TMP) emitted by the smelter. Considering the MP concentration in the grazed grass on the exposed site, it was concluded that cows absorb the MP not only from the grass but also from the soil surface. The results of a mild acidic leaching of the MP suggested that the particles were possibly submitted to a superficial dissolution in the abomasum, pointing at a potential route of transfer of the PTE originating from the TMP and leading into food chains. TMP were only a small part of the anthropogenic contamination having affected the soil and the dung. However, due to their unequivocal signature, TMP are a powerful tracer of the distribution of PTE in the different compartments constituting the food chains and the ecosystems. Furthermore, the measurement of the particle sizes gave evidence that a noticeable proportion of the MP could enter the respiratory tract.
显示更多 [+] 显示较少 [-]Co-contaminants and factors affecting the sorption behaviour of two sulfonamides in pasture soils
2013
Srinivasan, Prakash | Sarmah, Ajit K. | Manley-Harris, Merilyn
We investigated the effect of soil pH, organic carbon, ionic strength and steroid hormones on the sorption of sulfamethoxazole (SMO) and sulfachloropyridazine (SCP) in three pastoral soils of New Zealand. A model linking sorbate speciation with species-specific sorption coefficients describing the pH dependence of the apparent sorption coefficients was used to derive the fraction of each species of SMO. All soils displayed a decrease in sorption when pH was increased, with SMO exhibiting the highest sorption at pH 2. The cationic form of SMO appeared to sorb more close to pH ≥ pKa1 and, when pH ≥ pKa2 (6.5, 7.5 and 8.5) the anionic species seems to dominate, however, its sorption affinity to all soils was low. SMO sorption was affected by ionic strengths and organic carbon content, while the presence of hormones showed only a subtle decrease in SCP sorption in a selected model pasture soil.
显示更多 [+] 显示较少 [-]Short- and long-term temporal changes in soil concentrations of selected endocrine disrupting compounds (EDCs) following single or multiple applications of sewage sludge to pastures
2013
Rhind, S.M. | Kyle, C.E. | Ruffie, H. | Calmettes, E. | Osprey, M. | Zhang, Z.L. | Hamilton, D. | McKenzie, C.
Temporal changes in soil burdens of selected endocrine disrupting compounds were determined following application to pasture of either sewage sludge or inorganic fertilizer. Soil polycyclic aromatic hydrocarbon and polychlorinated biphenyl concentrations were not altered. Changes in concentrations of diethylhexyl phthalate (DEHP) and PBDEs 47 and 99 differed with season but concentrations remained elevated for more than three weeks after application, when grazing animals are normally excluded from pasture. It is concluded that single applications of sewage sludge can increase soil concentrations of some, but not all classes of EDCs, possibly to concentrations sufficient to exert biological effects when different chemicals act in combination, but patterns of change depend on season and soil temperature. Analysis of soil from pasture subjected to repeated sludge applications, over 13 years, provided preliminary evidence of greater increases in soil burdens of all of the EDC groups measured, including all of the PBDE congeners measured.
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